The SRM1801 from Mackie is a professional active subwoofer, designed to provide low frequency reinforcement for the SRM450v2 loudspeaker. The bass-reflex cabinet is made from solid plywood for excellent durability. It contains an 18" front-firing driver that can reproduce bass frequencies as low as 35Hz. An internal Class-D amplifier delivers 1000W of power for a strong performance with low distortion. The amp is highly efficient and lightweight to minimize the amount of waste heat that's produced and keep the subwoofer's weight down for better mobility.

Integrated active electronics include a precision crossover and tuning filters for an accurate bass response. The sub has dual XLR inputs for mono or stereo applications. It also has stereo high-pass and full range outputs for terrific versatility. User-adjustable level and polarity controls let you match the sub's performance to your specific application. LED indicators let you keep tabs visually on power, signal, overload, and thermal protection. The sub has a standard pole receptacle on top for mounting a loudspeaker, plus integrated handles on each side for convenient transportation.